L2.3.7: Adrenal Glands

• ADRENAL GLANDS

  ● Location: sits on top of the kidneys

  ● Has 2 regions:

  ○ Adrenal cortex

  ○ Adrenal medulla
• ○ Adrenal cortex

  ■ Outer glandular region that has 3 layers that produce CORTICOSTEROIDS

  • Zona glomerulosa: Outermost layer
  • Zona fasciculata: Middle layer
  • Zona reticularis: Innermost layer
• ○ Adrenal medulla

  ■ Inner neural tissue region
• HORMONES OF THE ADRENAL CORTEX

  ● MINERALOCORTICOIDS

  ● GLUCOCORTICOIDS

  ● SEX HORMONES
• ● MINERALOCORTICOIDS

  ○ Aldosterone

  ○ Produced by zona glomerulosa

  ○ Regulate mineral (salt) content in the blood, primarily Na+ and K+

  ○ Regulate water and electrolyte balance

  ○ Target organ is the kidney
• ● GLUCOCORTICOIDS

  ○ Cortisone and cortisol

  ○ Produced by the zona fasciculata

  ○ Promote normal cell metabolism

  ○ Help resist long-term stressors by increasing blood glucose levels (hyperglycemic hormones)

  ○ Anti-inflammatory properties, decreasing edema and pain

  ○ Released in response to increased blood levels of ACTH
• ● SEX HORMONES

  ○ Produced by the zona reticularis

  ○ Small amounts are made throughout life

  ○ Mostly androgens (male sex hormones)

  ○ Some are estrogens (female sex hormones)
• HORMONES OF THE ADRENAL MEDULLA

  ● 2 similar catecholamines

  ○ Epinephrine (adrenaline) and norepinephrine (non-adrenaline)

  ● They prepare the body to deal with short-term stress / fight-or-flight by

  ○ Increasing heart rate, blood pressure, and blood glucose levels

  ○ Dilating small passageways of lungs

  ● These events result in more oxygen and glucose in the blood and faster circulation to the organs